CN113138216B - Method for detecting nitrite in salted meat by electrochemical sensor based on cubic Ia3d structure mesoporous carbon - Google Patents

Method for detecting nitrite in salted meat by electrochemical sensor based on cubic Ia3d structure mesoporous carbon Download PDF

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CN113138216B
CN113138216B CN202110316210.1A CN202110316210A CN113138216B CN 113138216 B CN113138216 B CN 113138216B CN 202110316210 A CN202110316210 A CN 202110316210A CN 113138216 B CN113138216 B CN 113138216B
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孙宗保
刘小裕
张新爱
邹小波
牛增
潘浩东
李君奎
高云龙
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Abstract

The invention belongs to the technical field of meat product quality detection, and relates to a method for detecting nitrite in pickled meat by using an electrochemical sensor based on cubic Ia3d structure mesoporous carbon. The method comprises the following steps: firstly, synthesizing ordered mesoporous carbon CMK-8 with an Ia3d structure by adopting a hard template method, tightly combining gold nanoparticles AuNPs with positive electricity inside and outside an ordered pore channel of the CMK-8 with negative electricity through electrostatic adsorption to obtain a composite material, dripping the composite material on the surface of a treated glassy carbon electrode, performing infrared drying to obtain a working electrode, dripping a hemoglobin solution on the surface of the working electrode, drying, cleaning and drying again to obtain an electrochemical sensor, and being applied to detection of nitrite in pickled meat; the invention not only effectively improves NO 2 ‑ The sensitivity, stability and selectivity in the detection process can be repeatedly used, the operation steps are simple and quick, and the large-scale detection of the content of the nitrite in the food can be realized.

Description

Method for detecting nitrite in salted meat by electrochemical sensor based on cubic Ia3d structure mesoporous carbon
Technical Field
The invention belongs to the technical field of meat product quality detection, and particularly relates to a method for detecting nitrite in pickled meat by using an electrochemical sensor based on cubic Ia3d structure mesoporous carbon.
Background
The pickled meat products are widely favored by consumers because of rich nutrition, attractive aroma and unique taste. In the preparation process, nitrite is usually added as a color fixative of the meat product, so that the sensory color of the meat product is improved, the meat product is endowed with bright and bright red color and has special flavor; in addition, nitrite has inhibitory effect on various anaerobic clostridium bacteria, such as clostridium botulinum and lactobacillus viridis, and can prolong shelf life of meat product. However, the ingestion of excess amounts of nitrite can seriously affect human health. Nitrite is a strong oxidant, and can convert ferrous hemoglobin into high-iron hemoglobin after entering human blood, so that the high-iron hemoglobin loses the oxygen carrying function; in addition, nitrite can also be degraded and reacted with amino acid to generate nitrosamine substances with carcinogenicity. According to the regulations of Chinese national food safety standard (GB 2760-2014), the residual amount of nitrite in the pickled meat products is not more than 30mg/kg, 0.2-0.5g of nitrite can cause poisoning after being ingested by adults, and 3g of nitrite can kill. Therefore, an ultra-sensitive, rapid and accurate nitrite analysis method is established, and the method has important significance for guaranteeing the health of the public and the safety of the pickled meat products.
Currently, many conventional methods for detecting nitrite have been reported, including spectrophotometry, chromatography, capillary electrophoresis, etc., but most of them have the disadvantages of complicated and time-consuming detection process, large consumption of chemical reagents, expensive equipment, etc., which greatly limits their practical application. In recent years, fluorescence, electrochemistry, chemiluminescence, and the like have been reported for detection of nitrite. Among them, the electrochemical sensing technology is receiving attention due to its advantages of high sensitivity, fast detection speed, simple instrument, low price and easy miniaturization, and especially, the hemoglobin (Hb) -based sensor is considered to be a powerful tool for measuring nitrite. Hemoglobin is a heme-containing redox protein, and can be measured by measuring iron porphyrin and NO therein 2 - The nitrite is quantitatively detected by an electric signal generated by the oxidation-reduction reaction between the two. However, the hemoglobin sensor constructed at present still has the problems of weak hemoglobin molecule immobilization, high volatility, low sensor conductivity, poor stability and the like. In recent years, porous materials, especially ordered mesoporous carbon, have been used as electrodesThe modified material is concerned, has unique ordered mesoporous channel, adjustable pore size, large surface area, excellent conductivity and good biocompatibility, and provides a new hope for constructing a sensor with good performance. At present, mesoporous carbon with a two-dimensional hexagonal structure (p 6 mm) with long straight parallel pore channels is the most commonly used mesoporous carbon material in the design of the sensor, but no report has been made on constructing the sensor for detecting nitrite by using the mesoporous carbon with a three-dimensional bicontinuous cubic (Ia 3 d) structure. Therefore, the research selects the mesoporous carbon with the unique bicontinuous pore canal Ia3d structure to combine with the hemoglobin to construct the sensor, which makes it possible to develop an innovative sensing interface with enhanced electroanalytical performance.
Disclosure of Invention
The invention aims at the existing detection problems, such as complex operation process, long analysis time, easy interference, incapability of meeting the requirement of daily monitoring and the like of part of methods. The invention provides a method for detecting nitrite in pickled meat by using a single-step electrochemical sensor based on Ia3 d-structure mesoporous carbon, which is characterized in that a glassy carbon electrode modified by a three-dimensional bicontinuous cubic ordered mesoporous carbon (AuNPs-CMK-8) composite material anchored by gold nanoparticles with positive charges is used as a high-conductivity sensing interface, hemoglobin is used as an identification element, and ferriporphyrin and NO in the hemoglobin are measured 2 - The nitrite is quantitatively detected by an electric signal generated by the oxidation-reduction reaction. In general, the sensor is simple and convenient to operate, is rapid and sensitive, has excellent selectivity, high stability and extremely low detection limit, and provides a new opportunity for evaluating the residual amount of nitrite in the cured meat.
Specifically, the invention is realized by the following technical scheme:
(1) Preparing an ordered mesoporous carbon material with a bicontinuous cubic Ia3d structure by using mesoporous silica KIT-6 as a template and sucrose as a carbon source by adopting a hard template method, and recording the ordered mesoporous carbon material as a CMK-8 material;
(2) Synthesizing gold nanoparticles AuNPs with positive charges by using sodium borohydride as a reducing agent: cetyl trimethylammonium bromide (CTAB) aqueous solution was added to chloroauric acid solution (HAuCl) 4` 4H 2 In O) to obtainThe mixture was stirred in an ice bath for a period of time, then sodium borohydride solution (NaBH) was added 4 ) Continuously stirring the obtained mixed solution until the color of the solution is changed from light yellow to wine red, then carrying out centrifugal purification by pure water, and re-dispersing the precipitate obtained after the centrifugation in the pure water to obtain a gold nano solution which is marked as AuNPs;
(3) Mixing and stirring the CMK-8 material prepared in the step (1) and the AuNPs prepared in the step (2) for a period of time, standing the mixture of the two materials, centrifugally cleaning the mixture by using pure water, and dispersing precipitates collected after centrifugation into the pure water to obtain the nanogold-ordered mesoporous carbon composite material, which is marked as AuNPs-CMK-8;
(4) Dropwise adding the composite material AuNPs-CMK-8 obtained in the step (3) on the surface of the pretreated glassy carbon electrode, and drying under an infrared lamp to obtain a nanogold-ordered mesoporous carbon composite material modified electrode which is marked as AuNPs-CMK-8/GCE;
(5) Dissolving solid hemoglobin particles in a phosphate buffer solution to obtain a hemoglobin solution, coating the hemoglobin solution on the composite material modified electrode in the step (4), drying at room temperature, washing with pure water to remove unbound hemoglobin, and drying to obtain a hemoglobin/nanogold-ordered mesoporous carbon composite material modified working electrode which is marked as Hb/AuNPs-CMK-8/GCE;
(6) Firstly, preparing nitrite standard solutions with different concentrations, adopting a three-electrode system, taking the electrode prepared in the step (5) as a working electrode, and adopting a Differential Pulse Voltammetry (DPV) to detect the nitrite standard solutions with different concentrations to obtain a function relation between the nitrite concentration and corresponding response current, namely a nitrite detection standard curve;
(7) Preparing a salted meat sample, and pretreating to obtain a nitrite solution to be detected;
(8) And (4) detecting the nitrite to-be-detected solution obtained in the step (7) by adopting an electrochemical method in the step (6) to obtain a response current, and further calculating the concentration of nitrite in the to-be-detected solution according to the standard curve obtained in the step (6).
Wherein in the step (1)The specific preparation process for preparing the CMK-8 material by adopting the hard template method comprises the following steps: adding 1g KIT-6 powder into 5mL aqueous solution containing 1.5g sucrose, and adding 0.09mL H with 98% mass fraction 2 SO 4 Continuously stirring for 10 min to obtain a mixture, heating the mixture at 100 ℃ for 6 h, and then adjusting the temperature to 160 ℃ for 6 h; heating in two stages to obtain a heated mixture, adding 5mL of water solution dissolved with 1g of sucrose and 0.05mL of 98% H 2 SO 4 And stirred for 10 minutes; and repeating the two-stage heating operation to obtain a carbon-silicon compound, maintaining the carbon-silicon compound in a 900 ℃ tubular furnace for 6 hours in a nitrogen atmosphere, etching the carbonized product by using an HF solution with the mass fraction of 10% for 24 hours to remove the silicon dioxide template, washing the product by using pure water and ethanol, and drying the product to obtain the CMK-8 material.
Wherein the concentration of the hexadecyl trimethyl ammonium bromide solution in the step (2) is 10mmol/L, the concentration of the chloroauric acid solution is 1.0mmol/L, and the concentration of the sodium borohydride solution is 16mmol/L; the CTAB and HAuCl 4` 4H 2 O and NaBH 4 The volume ratio of the three is 2:15:2; all glassware used in the experimental process needs to be treated overnight by aqua regia and then is used after being completely washed by pure water.
Wherein the stirring in the ice bath in the step (2) is carried out for 15-20 min, and the stirring rotating speed is 400-500 rpm; the continuous stirring time is 50-60min, and the stirring rotating speed is 400-500 rpm; the centrifugation condition is 10000rpm for 10 minutes; the ratio of the precipitate to pure water is 1-5g.
Wherein the dosage ratio of the AuNPs to the CMK-8 material in the step (3) is 1mL: 1-5.0 mg; the mixing and stirring are carried out for 1 hour; the standing time is 24 hours; the centrifugation condition is 10000rpm for 10 minutes; the proportion of the precipitate to pure water in the step (3) is 1-6 g.
In the step (4), the diameter of the used glassy carbon electrode is 3mm, and the pretreatment method comprises the following steps: firstly, polishing a glassy carbon electrode on a polishing micro-cloth by using alumina with the grain diameter of 0.3 and 0.05 mu m, washing the glassy carbon electrode by using pure water, and respectively carrying out volume ratio of the polished glassy carbon electrode to the pure water in a range of 1:1, carrying out ultrasonic treatment for 5 minutes in a mixed solution of acetone and nitric acid, a sodium hydroxide solution with the mass fraction of 50% and pure water; and immersing the glassy carbon electrode after ultrasonic treatment in 0.50mol/L sulfuric acid solution, activating the electrode by adopting cyclic voltammetry under the condition of-0.2-0.6V for 10-60s, and removing residues on the surface of the electrode.
In the step (4), the dropping amount of the composite material AuNPs-CMK-8 is 10 mu L; the drying time under an infrared lamp is 3-5 min.
In the step (5), the pH value of the phosphate buffer solution is 7.4, and the concentration of the phosphate buffer solution is 0.1mol/L; the concentration of the hemoglobin solution is 3-20 mg/mL; the amount of the hemoglobin solution applied was 8. Mu.L.
The three-electrode system adopted in the step (6) takes a hemoglobin/nanogold-ordered mesoporous carbon modified electrode (AuNPs-CMK-8/GCE) as a working electrode, a platinum wire as a counter electrode and a silver/silver chloride electrode as a reference electrode; the electrochemical DPV detection parameters are as follows: the scanning window is 0.0 to-1.0V, the pulse amplitude is 0.05V, the pulse period is 0.2s, and the pulse width is 0.04s.
In the step (7), the pretreatment method of the salted meat sample specifically comprises the following steps: mincing the salted meat obtained by a quartering method by using a meat mincer, accurately weighing 5.0g of sample homogenate, adding the sample homogenate into 150mL of water, ultrasonically extracting for 30 minutes, and shaking once every 5 minutes to keep a solid phase completely dispersed; then, placing the uniform sample solution in a water bath at 75 ℃ for 15 minutes, taking out the uniform sample solution, standing the uniform sample solution to room temperature, and diluting the uniform sample solution to 200mL by using water; centrifuging the filtered solution at 10000rpm for 15 minutes, and finally diluting the supernatant by 10 times with 0.1mol/L phosphate buffer solution; wherein the pH value of the phosphate buffer solution is 3.0-9.0.
Compared with the prior art, the invention has the following beneficial effects:
(1) The 3-D bicontinuous cubic (Ia 3D) structure mesoporous carbon CMK-8 material has a unique bicontinuous mesoporous channel, a large specific surface area, good biocompatibility and excellent electrical conductivity, is favorable for serving as an immobilized substrate of a biological material and promoting direct electron transfer between nitrite and a hemoglobin active center so as to amplify signals.
(2) The nanogold with the positive surface is fixedly loaded in and out of the ordered pore canal of the mesoporous carbon with the negative surface through strong electrostatic adsorption and size matching, so that the composite material is combined more tightly.
(3) The sensor benefits from the rapid catalysis and specific recognition of the hemoglobin on the nitrite, and greatly improves the time efficiency and the anti-interference capability of the determination of the low-content nitrite.
(4) The synergistic effect of the mesoporous carbon material and the nano-gold can not only accelerate electron transfer to enhance electrochemical signals, but also provide a favorable biocompatibility microenvironment for hemoglobin to ensure biological activity and stability. In addition, the large specific surface area of the composite material exposes more active sites, and can adsorb more hemoglobin to enhance the catalysis effect on nitrite.
(5) The fabricated sensors showed a broad linear response in the range of 5.0nM to 1.0mM nitrite with a limit of detection as low as 2.1nM and were successfully used in the analysis of cured meat products, providing a promising tool for nitrite detection.
(6) The sensor provided by the invention effectively improves NO 2 - The sensitivity and stability in the detection process shorten the detection time, the nitrite response current can be obtained within 1min, the operation is simple, no special requirements are required for detection personnel, and the rapid detection on the nitrite content can be achieved.
Drawings
FIG. 1 is a process flow of AuNPs-CMK-8 composite material preparation.
A, B, C in FIG. 2 are HRTEM and corresponding Fourier Infrared transforms (inset) along [110], [111] and [311] directions, respectively, of Ia3d structural CMK-8 material.
FIG. 3 is a TEM image of AuNPs, in which the inset is a pictorial representation.
FIG. 4 is a nitrogen adsorption-desorption isotherm for CMK-8 and AuNPs-CMK-8, with the corresponding pore size distribution plots in the inset.
In FIG. 5, A is a SAXD graph of CMK-8 and AuNPs-CMK-8; b is the XRD pattern of CMK-8 and AuNPs-CMK-8.
FIG. 6 is an XPS map of AuNPs-CMK-8.
FIG. 7 shows that the NO in the pickled meat is treated by using GCE modified based on AuNPs-CMK-8 as a high-conductivity platform and Hb as a recognition element 2 - Schematic representation of electrochemical detection.
FIG. 8 is an optimized graph of the fixed concentration of Hb, with the inset being the corresponding bar graph.
FIG. 9A is the optimized CV curve of the ratio of AuNPs to CMK-8; and B is a corresponding histogram.
FIG. 10 is a graph of the optimized DPV for the pH of the base solution.
FIG. 11A Hb based sensor vs. different concentrations of NO 2 - DPV response plots (0, 5nM,10nM,50nM, 0.1. Mu.M, 0.5. Mu.M, 1. Mu.M, 5. Mu.M, 10. Mu.M, 50. Mu.M, 0.10mM,0.50mM, 1mM); b is the corresponding standard curve.
Detailed Description
The invention will be further elucidated by means of specific examples, without being limited thereto, in conjunction with the accompanying drawings.
Example 1:
(1) As shown in figure 1, a hard template method is adopted, mesoporous silica KIT-6 is used as a template, sucrose is used as a carbon source to prepare the ordered mesoporous carbon material CMK-8 with a bicontinuous cubic Ia3d structure, and the specific flow is as follows: 1g KIT-6 powder was added to 5mL of an aqueous solution containing 1.5g sucrose, and 0.09mL H was added to the mixture 2 SO 4 And stirring was continued for 10 minutes. The mixture was heated at 100 ℃ for 6 hours and then the temperature was raised to 160 ℃ for 6 hours. Next, 5mL of an aqueous solution in which 1g of sucrose was dissolved and 0.05mL of H were again added to the obtained sample 2 SO 4 And stirred for 10 minutes, repeating the heating operation: namely heating at 100 ℃ for 6 hours, and then increasing the temperature to 160 ℃ for 6 hours; thereafter, the obtained carbon-silicon composite was maintained in a tube furnace at 900 ℃ for 6 hours under a nitrogen atmosphere, and the carbonized product was etched with an HF solution at a mass fraction of 10% for 24 hours to remove the silica template, washed with pure water and ethanol, and dried, to obtain CMK-8 powder;
(2) Preparing gold nanoparticles with positive charges, auNPs: all glassware used was first treated overnight with aqua regia and rinsed thoroughly with pure water. Adding 2.0mL of 10mmol/L hexadecyl trimethyl ammonium bromide aqueous solution into 15mL of 1.0mmol/L chloroauric acid solution, violently stirring for 15 minutes in an ice bath at the rotating speed of 500rpm, then adding 2mL of freshly prepared 16mmol/L sodium borohydride solution, violently stirring the reaction mixture for 1 hour at the rotating speed of 500rpm again until the color of the solution is changed from light yellow to wine red, taking 2g of centrifugally purified precipitate, and re-dispersing in 1mL of pure water to obtain a gold nano solution, wherein the gold nano solution is recorded as AuNPs;
(3) Mixing and stirring the CMK-8 prepared in the step (1) and the AuNPs prepared in the step (2) for 1h, standing the mixture of the CMK-8 and the AuNPs for 24h, centrifuging and cleaning the mixture for 3 times by using pure water, collecting precipitates obtained after centrifugation, and dispersing 3g of the precipitates in 1mL of pure water to obtain the nanogold-ordered mesoporous carbon composite material which is marked as AuNPs-CMK-8;
(4) Characterizing the materials prepared in steps (1), (2) and (3); high power transmission electron microscopy of FIG. 2A, B, C along CMK-8 material [110]，[111]And [311]The crystal face direction shows a typical stripe-shaped and hexagonal arrangement structure and has a highly ordered mesoporous channel; the upper inset is an enlarged view of the transmission fringes, and the lower inset is the corresponding fourier-ir map. FIG. 3 shows the successful preparation of spherical AuNPs with an average particle size of 8.1 nm. FIG. 4 shows that the nitrogen adsorption-desorption isotherms for CMK-8 and AuNPs-CMK-8 are both typical Langmuir IV isotherms and that a hysteresis loop of H1 type with the presence of mesopores in the surface material is observed at relative pressures of about 0.40 to 0.98. Further, the specific surface area of CMK-8 was calculated to be 410m by BET 2 (iv)/g, auNPs-CMK-8 is 476m 2 The pore diameters obtained by the BJH model are all about 10nm. From SAXD in FIG. 5A at an angle ranging from 0.5 to 3.0, CMK-8 was observed to have diffraction peaks belonging to the (211), (321), (400), (332) and (431) planes of the Ia3d structure, and the AuNPs modified structure was not affected. The result shows that CMK-8 perfectly replicates the 3-D pore canal of the mesoporous silicon template. The XRD results (FIG. 5B) of the composite AuNPs-CMK-8 showed four characteristic diffraction peaks corresponding to the (111), (200), (220) and (311) crystal planes of AuNPs, respectively, in the range of 35-85 deg. compared to CMK-8It is clear that AuNPs have been successfully modified on CMK-8. The XPS results of FIG. 6 further demonstrate the successful preparation of the composite AuNPs-CMK-8;
(5) The glassy carbon electrode with a diameter of 3mm used was pretreated: firstly, polishing a glassy carbon electrode on a polishing micro-cloth by using alumina with the grain diameter of 0.3 and 0.05 mu m, washing the glassy carbon electrode by using pure water, and respectively carrying out volume ratio of the polished glassy carbon electrode to the pure water in a range of 1:1, carrying out ultrasonic treatment for 5 minutes in a mixed solution of acetone and nitric acid, a sodium hydroxide solution with the mass fraction of 50% and pure water; and immersing the glassy carbon electrode after ultrasonic treatment in 0.50mol/L sulfuric acid solution, activating the electrode by adopting cyclic voltammetry under the condition of-0.2-0.6V for 40s, and removing residues on the surface of the electrode. As shown in the electrode modification step of fig. 7, 10 μ L of the composite material AuNPs-CMK-8 obtained in the step (3) is dripped on the surface of the pretreated glassy carbon electrode, and is dried for 5min under an infrared lamp to obtain a nanogold-ordered mesoporous carbon composite material modified electrode, which is marked as AuNPs-CMK-8/GCE;
(6) Dissolving hemoglobin (Hb) in 1mL of phosphate buffer solution with the concentration of 0.1mol/L (pH 7.4), coating 8 mu L of the hemoglobin (Hb) on the composite material modified electrode in the step (5), drying the composite material modified electrode at room temperature, slightly washing the composite material modified electrode with pure water to remove unbound hemoglobin, and drying the composite material modified electrode to obtain a hemoglobin/nanogold-ordered mesoporous carbon composite material modified working electrode which is recorded as Hb/AuNPs-CMK-8/GCE; in order to improve the detection signal of nitrite, hemoglobin solutions (3-20 mg/mL) with different concentrations were respectively immobilized on the sensor surface, as can be seen from the comparison of the results in fig. 8, the hemoglobin solution with the immobilized concentration of 13mg/mL showed the largest DPV response, and the hemoglobin solution with the concentration of 13mg/mL was selected in this example;
(7) In order to improve the electron transmission rate in detection, the volume-mass ratio (1:1-1:5) of AuNPs to CMK-8 is optimized to improve the sensitivity. As shown in the results of FIG. 9, the maximum response current is obtained when the volume-mass ratio of AuNPs to CMK-8 is 1:3, and when the ratio is higher than 1:3, the current response is not obviously increased, so that the sensor is established by selecting the ratio of AuNPs to CMK-8 as 1:3;
(8) In order to improve the response current, the study performed cyclic voltammetric scanning in the range of-1.0 to 1.0V using phosphate buffer solutions with pH values of 3.0,4.0,5.0,6.0,7.0,9.0 as the base solutions. As shown in FIG. 10, the oxidation-reduction peak potential gradually shifted in the negative direction as the pH of the solution increased, and the highest reduction peak was reached at pH 4.0. Therefore, pH 4.0pH was selected as the detection solution;
(9) And (3) adopting a three-electrode system, taking the Hb/AuNPs-CMK-8/GCE electrode prepared in the step (6) as a working electrode, a platinum wire as a counter electrode, and a silver/silver chloride electrode as a reference electrode. Different concentrations of nitrite standard solutions (0, 5nM,10nM,50nM, 0.1. Mu.M, 0.5. Mu.M, 1. Mu.M, 5. Mu.M, 10. Mu.M, 50. Mu.M, 0.10mM,0.50mM, 1mM) were assayed using Differential Pulse Voltammetry (DPV) with optimal parameters as follows: the scanning window is 0.0 to-1.0V, the pulse amplitude is 0.05V, the pulse period is 0.2s, and the pulse width is 0.04s. FIG. 11 shows the obtained function relationship between nitrite with different concentrations and corresponding response currents, and the standard curve y =0.3487x +3.5261, differential pulse volt-ampere response (Δ I) and NO is obtained 2 - The logarithmic (log) value of the concentration has a good linear relation between 5nM and 1mM, and the detection Limit (LOD) is as low as 2.1nM, so that the requirement of monitoring the nitrite content in the cured meat in real time can be met;
(10) Preparing 5 cured meat samples and carrying out pretreatment to obtain a nitrite solution to be detected: mincing the salted meat obtained by a quartering method by using a meat mincer, accurately weighing 5.0g of sample homogenate, adding the sample homogenate into 150mL of water, ultrasonically extracting for 30 minutes, and shaking once every 5 minutes to keep a solid phase completely dispersed; thereafter, the homogeneous sample solution was placed in a water bath at 75 ℃ for 15 minutes, taken out to stand to room temperature, and diluted with water to 200mL. Centrifuging the filtered solution at 10000rpm for 15 minutes, and finally diluting the supernatant by 10 times with 0.1mol/L of a phosphate buffer solution with pH 4.0;
(11) And (3) detecting the actual sample nitrite solution to be detected obtained in the step (10) by adopting the electrochemical DPV method in the step (9), and repeatedly measuring each sample for 3 times. And (4) calculating the concentration of the nitrite in the solution to be detected according to the standard curve obtained in the step (9) by using the obtained response current. The results show the mean values determined by electrochemical methodsClose to the results obtained from UV-visible spectrophotometry (table 1) and the Relative Error (RE) maximum was less than 4.27%. Shows that the sensor can be well used for NO in pickled meat 2 - Analysis of (2).
TABLE 1 actual sample NO 2 - Content analysis (n = 3)
Figure BDA0002991354420000071
Figure BDA0002991354420000081
The above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention; thus, while the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted; all such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.

Claims (10)

1. A method for detecting nitrite in salted meat by an electrochemical sensor based on cubic Ia3d structure mesoporous carbon is characterized by comprising the following steps:
(1) Preparing an ordered mesoporous carbon material with a bicontinuous cubic Ia3d structure by using mesoporous silica KIT-6 as a template and sucrose as a carbon source by adopting a hard template method, and marking the ordered mesoporous carbon material as a CMK-8 material;
(2) Adding hexadecyl trimethyl ammonium bromide aqueous solution into chloroauric acid solution, stirring the obtained mixed solution in ice bath for a period of time, then adding sodium borohydride solution to obtain mixed solution, continuously stirring until the color of the solution is changed from light yellow to wine red, then carrying out centrifugal purification by using pure water, and re-dispersing the precipitate obtained after centrifugation in the pure water to obtain gold nano solution, which is recorded as AuNPs;
(3) Mixing and stirring the CMK-8 material prepared in the step (1) and the AuNPs prepared in the step (2) for a period of time, standing the mixture of the two materials, centrifugally cleaning the mixture by using pure water, and dispersing precipitates collected after centrifugation into the pure water to obtain the nanogold-ordered mesoporous carbon composite material, which is marked as AuNPs-CMK-8;
(4) Dropwise adding the composite material AuNPs-CMK-8 obtained in the step (3) on the surface of the pretreated glassy carbon electrode, and drying under an infrared lamp to obtain a nanogold-ordered mesoporous carbon composite material modified electrode which is marked as AuNPs-CMK-8/GCE;
(5) Dissolving solid hemoglobin particles in a phosphate buffer solution to obtain a hemoglobin solution, coating the hemoglobin solution on the composite material modified electrode in the step (4), drying at room temperature, washing with pure water to remove unbound hemoglobin, and drying to obtain a hemoglobin/nanogold-ordered mesoporous carbon composite material modified working electrode which is marked as Hb/AuNPs-CMK-8/GCE;
(6) Preparing nitrite standard solutions with different concentrations, adopting a three-electrode system, taking the electrode prepared in the step (5) as a working electrode, and adopting a differential pulse voltammetry to detect the nitrite standard solutions with different concentrations to obtain a functional relation between the nitrite concentration and corresponding response current, namely a nitrite detection standard curve;
(7) Preparing a salted meat sample, and pretreating to obtain a nitrite solution to be detected;
(8) And (5) detecting the nitrite solution to be detected obtained in the step (7) by adopting an electrochemical method in the step (6), obtaining a response current, and further calculating the concentration of nitrite in the solution to be detected according to the standard curve obtained in the step (6).
2. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3d mesoporous carbon as claimed in claim 1, wherein in step (1), the CMK-8 material prepared by the hard template method comprises the following specific steps: adding 1g KIT-6 powder to 5mL aqueous solution containing 1.5g sucrose, and adding 0.09mL 98% H to the mixture 2 SO 4 And is continuousStirring for 10 min to obtain a mixture, heating at 100 deg.C for 6 hr, and adjusting the temperature to 160 deg.C for 6 hr; heating in two stages to obtain a heated mixture, adding 5mL of water solution dissolved with 1g of sucrose and 0.05mL of 98% H 2 SO 4 And stirring for 10 minutes; and repeating the two-stage heating operation to obtain a carbon-silicon compound, maintaining the carbon-silicon compound in a 900 ℃ tubular furnace for 6 hours in a nitrogen atmosphere, etching the carbonized product by using an HF solution with the mass fraction of 10% for 24 hours to remove the silicon dioxide template, washing the product by using pure water and ethanol, and drying the product to obtain the CMK-8 material.
3. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein the concentration of the cetyltrimethylammonium bromide solution in the step (2) is 10mmol/L, the concentration of the chloroauric acid solution is 1.0mmol/L, and the concentration of the sodium borohydride solution is 16mmol/L; the CTAB and HAuCl 4` 4H 2 O and NaBH 4 The volume ratio of the three is 2:15:2; all glassware used in the experimental process needs to be treated overnight by aqua regia and then is used after being completely washed by pure water.
4. The method for detecting nitrite in pickled meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein in step (2), the mixture is stirred in an ice bath for a period of 15-20 min at a stirring speed of 400-500 rpm; the continuous stirring time is 50-60min, and the stirring rotating speed is 400-500 rpm; the centrifugation condition is 10000rpm for 10 minutes; the ratio of the precipitate to pure water is 1-5g.
5. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3d structure mesoporous carbon as claimed in claim 1, wherein the dosage ratio of AuNPs to CMK-8 material in step (3) is 1mL: 1-5.0 mg; the mixing and stirring are carried out for 1h; the standing time is 24 hours; the centrifugation condition is 10000rpm and is maintained for 10 minutes; the ratio of the precipitate to pure water is 1-6 g.
6. The method for detecting nitrite in salted meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein in the step (4), the diameter of the glassy carbon electrode is 3mm, and the pretreatment method comprises the following steps: firstly, polishing a glassy carbon electrode on a polishing micro-cloth by using alumina with the grain diameter of 0.3 μm and 0.05 μm, washing the glassy carbon electrode by using pure water, and then respectively carrying out volume ratio of the glassy carbon electrode to the alumina in a range of 1:1, carrying out ultrasonic treatment for 5 minutes in a mixed solution of acetone and nitric acid, a sodium hydroxide solution with the mass fraction of 50% and pure water; and immersing the glassy carbon electrode subjected to ultrasonic treatment into 0.50mol/L sulfuric acid solution, and activating the electrode by adopting a cyclic voltammetry method under the condition of-0.2-0.6V for 10-60s.
7. The method for detecting nitrite in pickled meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein in the step (4), the dosage of the composite material AuNPs-CMK-8 added dropwise is 10 μ L; the drying time under an infrared lamp is 3-5 min.
8. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3d structure mesoporous carbon as claimed in claim 1, wherein the phosphate buffer solution has a pH value of 7.4 and a concentration of 0.1mol/L; the concentration of the hemoglobin solution is 3-20 mg/mL; the amount of the hemoglobin solution applied was 8. Mu.L.
9. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein the three-electrode system adopted in step (6) uses Hb/AuNPs-CMK-8/GCE as a working electrode, a platinum wire as a counter electrode and a silver chloride electrode as a reference electrode; electrochemical DPV detection parameters were: the scanning window is 0.0 to-1.0V, the pulse amplitude is 0.05V, the pulse period is 0.2s, and the pulse width is 0.04s.
10. The method for detecting nitrite in cured meat by using the electrochemical sensor based on cubic Ia3 d-structured mesoporous carbon as claimed in claim 1, wherein in step (7), the pretreatment method of the cured meat sample specifically comprises the following steps: mincing salted meat obtained by a quartering method by using a meat grinder, weighing 5.0g of sample homogenate, adding the sample homogenate into 150mL of water, performing ultrasonic extraction for 30 minutes, and shaking once every 5 minutes to keep a solid phase completely dispersed; then, placing the uniform sample solution in a water bath at 75 ℃ for 15 minutes, taking out and standing to room temperature, and diluting to 200mL by using water; centrifuging the filtered solution at 10000rpm for 15 minutes, and finally diluting the supernatant by 10 times with 0.1mol/L phosphate buffer solution; wherein the pH value of the phosphate buffer solution is 3.0-9.0.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104502583A (en) * 2015-01-09 2015-04-08 江苏大学 Carbon nano tube/nanogold composite membrane electrochemical immunosensor and application thereof
CN107228889A (en) * 2017-06-14 2017-10-03 上海海洋大学 The preparation and application of a kind of cobalt oxide/mesoporous carbon composite material electrochemical sensor
CN108760859A (en) * 2018-06-11 2018-11-06 海南师范大学 A kind of preparation method and application of hemoglobin and mesoporous carbon-gold nano star composite material modified electrode
CN112034026A (en) * 2020-08-04 2020-12-04 大连理工大学 Electrochemical sensor for detecting nitrite, preparation method and application

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180284108A1 (en) * 2017-04-01 2018-10-04 Michael Joseph Pugia Method for complete and fragmented markers
TWI707142B (en) * 2017-07-07 2020-10-11 東吳大學 A detection device for detecting the concentration of nitrite

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104502583A (en) * 2015-01-09 2015-04-08 江苏大学 Carbon nano tube/nanogold composite membrane electrochemical immunosensor and application thereof
CN107228889A (en) * 2017-06-14 2017-10-03 上海海洋大学 The preparation and application of a kind of cobalt oxide/mesoporous carbon composite material electrochemical sensor
CN108760859A (en) * 2018-06-11 2018-11-06 海南师范大学 A kind of preparation method and application of hemoglobin and mesoporous carbon-gold nano star composite material modified electrode
CN112034026A (en) * 2020-08-04 2020-12-04 大连理工大学 Electrochemical sensor for detecting nitrite, preparation method and application

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Amperometric biosensor for hydrogen peroxide and nitrite based on hemoglobin immobilized on one-dimensional gold nanoparticle;Jianmin Hong等;《Sensors and Actuators B: Chemical》;20090503;第140卷;第222–226页 *
Electrochemical microfluidic immunosensor based on TES-1 AuNPs@Fe3O4 and CMK-8 for IgG anti-Toxocara canis determination;Claudio F. Jofre等;《Analytica Chimica Acta》;20200201;第1-37页 *

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